Blast-heater.



W. W. KEMP & W.-H. VAN HOHN BLAST HEATER.

- APPLICATION FILED JUNE 23. 1916.

1,244,863., Patented 001;. 30, 1917].

srairns PATENT OFFICE.

wrnnmm warmer: xnnzr Ann winner: H. van norm, or nnn'rmonn, MARY AND.

BLAST-HEATER.

Laeaees.

Application filed June 23, 1916. Serial No. 105,526.

To all whom it my concern:

Beit known that we, WILLIAM Wanmcn KEMP and WILLIAM H. VAN HORN,citizens of the United States, residing atBaltimore,

in the county of Baltimore City and State of Maryland, have invented newand useful Improvements in Blast-Heaters, of which the following is aspecification.

This invention relates to heaters, and has as its object to provide aheater in which a blast flame is utilized to create and maintain thecirculation of a heated. gaseous-medium through an endless passage, theheated medium being repeatedly returned to the flame or blast to beheated thereby. By

. thus returning the gaseous medium or prodnets of combustion andrepeatedly heating them, a great economy in the consumption of fuel isobtained, for after passing through the endless passage, the combustionproducts still possess considerable heat, and less fuel is required toheat them to the desired temperature than if fresh atmospheric air wereused. The heated gases or products.

of combustion circulate rapidly through the radiator, the heatdistribution is uniform and the temperature of the device may be easilyand perfectly controlled, while, at the same time, the discharge of theproducts of combustion and dust into the chamber to be heated may beavoided.

The above and other objects of this invention are obtained by' thestructure described in the following specification and. illustrated inthe accompanying drawings, and where- Figure 1 is an elevational view ofour device, a portion of the heater being broken away to disclose theburner.

Fig. 2 is a view similar to Fig. 1, showing a slightly differentconstruction.

, In the drawings, like numerals represent like parts in the severalviews. We have shown, in the present instance, our improved heater ascomprising a radiator but, of course, our apparatus is susceptible tovarious changes, and the method of heating herein described may becarried out in appa ratus other than radiators .10 designates aradiating pipe which is endless in that it forms a continuous passagethrough which the heated products of combustion are adapted tocirculate.The radiating pipe may be of any suitable construction, and may beconstructed of wrought iron or any other suitable material. In thepresent instance,

Specification of Letters Patent.

Patented Oct. 30,- 1917.

' we have shown-the pipe as laid out to form -or tortuous path of anysuitable shape depending on the use to which it is to be put.

Mounted within the radiating pipe is a burner tube 11 retained centrallywithin the pipe by means of brackets or spiders 12. The burner tube 11is mounted preferably at one of the angles or elbows of the radiatingpipe with its inner end extending longitudinally into the inlet portion13 of the radiating pipe and its outer end projecting into the elbow,the latter end being in alinemeut with the through opening in the returnportion 14 of the radiating pipe. Extending through an openin 15 in thewall of the radiating pipe, an in alinement' with the tube 11 is a gaspipe 16 carrying on its inner end a burner '17 which may be of anysuitable construction. The pipe 16 leads from a suitable air and gasmixing device, and while any such suitable device may be employed,

we prefer to connect the pipe 16 to a gas and air mixing apparatus ofthe general type disclosed in Patent No. 1,141,466, dated June 1, 1915,granted to W. H. Van Horn and Wm. W. Kemp. In the device described inthe last-mentioned patent, air and gas are mixed in such proportions,that the mixture is self-sustaining; that is, sufiicient oxygen is inthe mixture to completely burn the gas mixed therewith and no outsidesupporter of combustion is required. The pipe 16 has a regulating andshut-off cock 17' which may be ofany desired form, and which has anoperating handle 18 provided with a.pointer 19 which is adapted to moveover an indirating scale upon the plate or member 20 when the handle isturned. 7

In Fig. 2, we have shown a device similar to that disclosed in Fig.1,'but in this embodiment of the invention the radiator is disclosed asmounted horizontally (although it may be mounted vertically) in ajapanning oven, the japanning oven being conventionally shown by theline 21. It is, of course, obvious that the device herein disclosed isapplicable for use in a great variety of apparatus, and we have shownthe same applied in Fig. 2 to a japanning oven by way of illustrationonly. In such oven, it is particularly desirable to eliminateintroduction of products of combustion or dust into the space in whichthe articles to be japanned are located, to obtain a relaing pipe andits in ct end lies within tively high heat and to heat the oven uniformly, and with the use of our device, these requisites are obtained.In this embodiment, the radiator is shown as provided with a neckportion 22 extending through an opening in the wall of the japanningoven and having a chamber 23 with which the ends of the radiating pipe10 are in communication, and by this construction, the exhaust gases maybe discharged through the opening 15 about the pipe 16 into theatmosphere and thus introduction of these exhaust gases into the oven iseliminated. The tube 11 is so mounted that its outlet'end lies ithin theinlet ortion 13 of the radiatiot e chamber 23.

When it is desired to place the device disclosed in the drawings inoperation, the handle 18 is turned (the amount to which it is turnedbeing indicated by the position of the pointer over the scale), to admitthe air and gas mixture from its source (not shown) to the burner whereit is ignited. The mixture of air and gas produces a flame which isself-sustaining, and the mixture is projected into the tube 11 withconsiderable pressure, thereby causing the products of combustion totravel through the tube 11 with considerable velocity. A strong suctionis thus created about the burner which draws or entrains atmospheric airinto the tube 11 and about the burner. The prod ucts'of combustiontogether with the entrained air are discharged from the outlet end ofthe tube 11 into the pipe 10 and the same circulate through the pipe 10with considerable rapidity. Immediately after starting the burner, aninflux of air through the opening 15 is noticeable, and then for a shortperiod of time a noticeable exit of air through the opening-15 may beobserved,

' this exit of air being due to the fact that the products of combustionfrom the burner forces or scavenges the pipe of the air with which thesame is filled when not in operation. After. the device is in operationa short time, the products of combustion are repeatedly circulatedthrough the radiating pipe, a portion of the products of combust1onafter passing through the return portion 14 of pipe 10 being entrainedor drawn into the pipe 11 about the burner 17 and a secondary suctionbeing created in the space between the tube 11 and the surrounding wallof the radiating pipe 10 duetothe blast discharge of the products ofcombustion from the outlet end of tube 11. During the normal operationof the device, a discharge of the excess combustion products through theopening 15 takes place, this being due, of course, to the fact that agaseous mixture is continuously admitted into the-heater .through theburner 17.

It will be noted that during the normal I a i L operation of the devlce,an or other gas 1s r not admitted to the radiator except through theburner 17, the gaseous mixture admitted to the burner being in suchproportion that the flame is self-supporting. The discharge ofcombustion products from the burner is such as to force the gaseousmedium within the pipe 10 before them, and, at the same time, a suctionaction is created about the burner and about the tube 11 which draws thegaseous products of combustion passing through the return portion 14into the inlet portion 13 of the radiator. These gases are again andagain circulated through the radiating pipe and the circulationthroughout the entire length of the radiating p1pe is very rapid so thatthe heat is uniformly distributed. In place of discharging the productsof combustion from the pipe after completing the circuit and drawing'infresh air, the products of combustion are again heated by the hot blastfrom the burner and as the combustion products retain some of theirheat, itrequires less fuel to heat them to any given degree than ifoutside air were utilized.

When the radiator is applied to a japanning or other oven, the neckportion 22 preferably extends through an opening in the wall of the ovenso that excess products of combustion discharged from the radiator passoif into the atmosphere and none of the products of combustion enter.into-the compartment in which the articles are treated, and thus dustand the like due to the burning of fuel, or dust which might beintroduced dueto draft currents or stirred up thereby are entirelyeliminated. It is, 4

. clalms.

What. is claimed is: p v

1. In combination, a member having an endless substantially closedpassage from which air is excluded and provided with an opening for{exhaust purposes only, and means for discharging a flame forwardly intosaid passage at a pressure greater than that of the atmosphere forreheating and causing circulation of the products of combustion therein.J

2.-In combination, a member having an endless substantially closedpassage having an exit opening, and means for discharging an ignitedflame sustainin mixture 4 at a pressure greater than that o theatmosphere into said passage and in a direction therein to cause theproducts oii combustion to flow about said passage.

5. A radiator comprisingan endlessfpipe 3. In; combination, an endlesstube hav ing a, continuous substantially closed pas sage provided withanexit opening for ex* haust purposes only, and means within the passagefor discharging an ignited aseous flame-sustaining mixture therein un errelatively high pressure in a direction to cause the products ofcombustion to flow about the passage at relatively high velocity.

4. A radiator comprising a pipe having a substantially closed. endlesspassage from which air is excluded and provided with an opening forexhaust purposes only, and

means for discharging a hot flame under pressure greater thanatmospheric into saidpassage in a direction, to cause the products ofcombustion to circulate about the passage.

having a continuous substantially blosed passage, means, within thepassage for dis- "fcharging an ignited gaseous flame-sustaining mixtureunder relatively high pressure therein'in a direction to cause theproductionsof combustion to-oirculate about said passage, said pipehaving at its return side of combustion discharge.

6. A radiator comprising an endless radiating pipe having a continuous.passage an opening through which excess products from which air isexcluded and provided with an opening for exhaust purposes only,

I endless substantially closed passage romdirection to causeefirculation of the and a'bua'ner within the passage adapted todischarge an ignited. gaseous flame-sustaining mixture under pressureforwardly therein to create a circulation ofthe products of combustionandrepeatedly heat them.

'7. In combination, a member havin 'an which air is excluded, a tube insaid passage spaced from the wall thereof, and means for discharging aflame into the tube under pressure greater than atmospheric and inaproducts of combustion rough the passage, and

an outlet in said passage for permitting dis charge of the products ofcombustion.

8. In combination, a member having an endless substantially closedpassage, a tube 4 within and lengthwise'of the passage and speced fromthe wall thereof, and a burner extending into said tube for dischargingan ignited gaseous flame-sustaining mixture into said tube underpressure greater than atmospheric and in 'a direction to entrainproducts of combustion into the tube and into the space aboutfthe tube,said passage 1 means for dischargin poses at its return side. 10. Aradiator comprising an endless pipe of heat conducting material havingacontinuous passage from which air is excluded and also having anopening for exhaust purposes only; a tube within the passage spaced fromthe wall thereof, and a burner extending into the tube and adapted todischarge an ignited gaseous flame-sustaining mixture underpressureforwardly therein to entrain products of combustion into the tube and inthe space between the tube and the wall of the pipe and thus create acirculation of the products o'f combustionv therein at relatively highvelocity so that they are repeatedly heat-ed.

' 11. In combination, a chamber, an endless substantially closed pipewithin the chamber having a continuous passage from which air isexcluded, said passage having an outletv opening for exhaust purposesonly, and means within the passage for discharging an ignited gaseousflame-sustaining mixture under pressure greater than atmospheric intothe passage in a direction to cause the.

products of combustion to flowthrough the passage.

12. In combination, a chamber, an oven, a pipe having an endlesssubstantially closed passage from which air is excluded, said passagehaving an outlet opening for exhaust purposes only in the return .sideof the pipe and outside of said chamber, and

a gaseous flame sustaining mixture into t e passage under pressuregreater than atmospheric and in a direction to cause circulation of theproducts of combustion about the passage.

In testimony whereof we have set our hands'in presence of twosubscribing witnesses. 1

WILLIAM WALLACE KEMP.

. WHJLIAM H. VAN HORN.

Witnesses:

' H. G. Bisnor,

MARY URsI hereunto

